Fix auto-layout of space views (#3524)

### What
* Closes #3521

The problem was `auto_layout` being set to `false` too early.

This fix required a change to `egui_tiles`, so a patch-release of that
needs to be done before we publish rerun 0.9:

* rerun-io/egui_tiles#29

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [ ] I have tested [demo.rerun.io](https://demo.rerun.io/pr/3524) (if
applicable)

- [PR Build Summary](https://build.rerun.io/pr/3524)
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preview](https://rerun.io/preview/8abfdc1bbcd6ed36786600e59705f90b25017f7e/docs)
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Cargo.toml

@@ -164,3 +164,6 @@ debug = true
 # If that is not possible, patch to a branch that has a PR open on the upstream repo.
 # As a last resport, patch with a commit to our own repository.
 # ALWAYS document what PR the commit hash is part of, or when it was merged into the upstream trunk.
+
+
+egui_tiles = { git = "https://github.com/rerun-io/egui_tiles.git", rev = "b34432b2ff68eb2e087a41b241d70ec367a09334" }

crates/re_viewport/src/blueprint_components/viewport.rs

@@ -60,7 +60,7 @@ re_log_types::arrow2convert_component_shim!(SpaceViewMaximized as "rerun.bluepri
 ///     ])
 /// );
 /// ```
-#[derive(Clone, Default, ArrowField, ArrowSerialize, ArrowDeserialize)]
+#[derive(Clone, ArrowField, ArrowSerialize, ArrowDeserialize)]
 pub struct ViewportLayout {
     #[arrow_field(type = "SerdeField<std::collections::BTreeSet<SpaceViewId>>")]
     pub space_view_keys: std::collections::BTreeSet<SpaceViewId>,
@@ -71,6 +71,16 @@ pub struct ViewportLayout {
     pub auto_layout: bool,
 }
 
+impl Default for ViewportLayout {
+    fn default() -> Self {
+        Self {
+            space_view_keys: Default::default(),
+            tree: Default::default(),
+            auto_layout: true,
+        }
+    }
+}
+
 re_log_types::arrow2convert_component_shim!(ViewportLayout as "rerun.blueprint.ViewportLayout");
 
 #[test]

crates/re_viewport/src/viewport.rs

@@ -141,23 +141,31 @@ impl<'a, 'b> Viewport<'a, 'b> {
             &mut blueprint.tree
         };
 
-        let mut tab_viewer = TabViewer {
-            viewport_state: state,
-            ctx,
-            space_views: &mut blueprint.space_views,
-            maximized: &mut blueprint.maximized,
-        };
-
         ui.scope(|ui| {
             ui.spacing_mut().item_spacing.x = re_ui::ReUi::view_padding();
 
             re_tracing::profile_scope!("tree.ui");
-            let tree_before = tree.clone();
+
+            let mut tab_viewer = TabViewer {
+                viewport_state: state,
+                ctx,
+                space_views: &mut blueprint.space_views,
+                maximized: &mut blueprint.maximized,
+                edited: false,
+            };
+
             tree.ui(&mut tab_viewer, ui);
 
             // Detect if the user has moved a tab or similar.
             // If so we can no longer automatically change the layout without discarding user edits.
-            if blueprint.auto_layout && *tree != tree_before {
+            let is_dragging_a_tile = tree.dragged_id(ui.ctx()).is_some();
+            if tab_viewer.edited || is_dragging_a_tile {
+                if blueprint.auto_layout {
+                    re_log::trace!(
+                        "The user is manipulating the egui_tiles tree - will no longer auto-layout"
+                    );
+                }
+
                 blueprint.auto_layout = false;
             }
         });
@@ -239,6 +247,9 @@ struct TabViewer<'a, 'b> {
     ctx: &'a mut ViewerContext<'b>,
     space_views: &'a mut BTreeMap<SpaceViewId, SpaceViewBlueprint>,
     maximized: &'a mut Option<SpaceViewId>,
+
+    /// The user edited the tree.
+    edited: bool,
 }
 
 impl<'a, 'b> egui_tiles::Behavior<SpaceViewId> for TabViewer<'a, 'b> {
@@ -444,6 +455,12 @@ impl<'a, 'b> egui_tiles::Behavior<SpaceViewId> for TabViewer<'a, 'b> {
             ..Default::default()
         }
     }
+
+    // Callbacks:
+
+    fn on_edit(&mut self) {
+        self.edited = true;
+    }
 }
 
 fn space_view_ui(

crates/re_viewport/src/viewport_blueprint.rs

@@ -177,6 +177,10 @@ impl<'a> ViewportBlueprint<'a> {
     }
 
     pub fn mark_user_interaction(&mut self) {
+        if self.auto_layout {
+            re_log::trace!("User edits - will no longer auto-layout");
+        }
+
         self.auto_layout = false;
         self.auto_space_views = false;
     }
@@ -205,7 +209,7 @@ impl<'a> ViewportBlueprint<'a> {
 
         if self.auto_layout {
             // Re-run the auto-layout next frame:
-            re_log::trace!("No user edits yet - will re-run auto-layout");
+            re_log::trace!("Added a space view with no user edits yet - will re-run auto-layout");
             self.tree = Default::default();
         } else {
             // Try to insert it in the tree, in the top level:
@@ -214,11 +218,14 @@ impl<'a> ViewportBlueprint<'a> {
                 if let Some(egui_tiles::Tile::Container(container)) =
                     self.tree.tiles.get_mut(root_id)
                 {
+                    re_log::trace!("Inserting new space view into root container");
                     container.add_child(tile_id);
                 } else {
                     re_log::trace!("Root was not a container - will re-run auto-layout");
-                    self.tree = Default::default(); // we'll just re-initialize later instead
+                    self.tree = Default::default();
                 }
+            } else {
+                re_log::trace!("No root found - will re-run auto-layout");
             }
         }
 

crates/re_viewport/src/viewport_blueprint_ui.rs

@@ -37,7 +37,7 @@ impl ViewportBlueprint<'_> {
                 egui_tiles::Tile::Pane(space_view_id) => space_view_id == focus_tab,
                 egui_tiles::Tile::Container(_) => false,
             });
-            re_log::trace!("Found {focus_tab}: {found}");
+            re_log::trace!("Found tab {focus_tab}: {found}");
         }
 
         for tile_id in remove {
@@ -128,6 +128,10 @@ impl ViewportBlueprint<'_> {
         }
 
         if visibility_changed {
+            if self.auto_layout {
+                re_log::trace!("Container visibility changed - will no longer auto-layout");
+            }
+
             self.auto_layout = false; // Keep `auto_space_views` enabled.
             self.tree.set_visible(tile_id, visible);
         }
@@ -193,6 +197,10 @@ impl ViewportBlueprint<'_> {
         item_ui::select_hovered_on_click(ctx, &response, &[item]);
 
         if visibility_changed {
+            if self.auto_layout {
+                re_log::trace!("Space view visibility changed - will no longer auto-layout");
+            }
+
             self.auto_layout = false; // Keep `auto_space_views` enabled.
             self.tree.set_visible(tile_id, visible);
         }